Regional Scale Erosion Assessment of a Sub-tropical Highland Segment in the Western Ghats of Kerala, South India

Revised Universal Soil Loss Equation (RUSLE) has been used in combination with remote sensing and GIS techniques to assess the spatial pattern and annual rate of soil erosion in the Munnar Forest Division in Western Ghats, Kerala, India. The RUSLE takes into account several factors such as rainfall, soil erodibility, slope length and steepness, land cover and erosion control practice for soil erosion prediction. Maximum soil loss of 109.31 t h(-1)y(-1) and the areas with extreme erosion (erosion is higher than 50 t h(-1)y(-1)) are confined to 11.46% of the total area, while the area occupied by severe erosion (erosion rate between 25 and 50 t h(-1)y(-1)) is 27.53%. The high rate of annual soil erosion is associated with areas of high terrain alteration from the plantation activities and highly elevated hills/plateau margins with steep side slopes. Such an output is highly useful in decision making context to avoid land acquisition in erosion risk areas, or, alternatively, to recommend soil conservation measures to reduce soil loss, if developmental activities are to be continued at high soil erosion risk areas.